Apparatus for producing titanium tetrachloride and other halides



APPARATUS FOR PRODUCING TITANIUM TETRACHLORIDE AND OTHER HALIDES FiledJan. 18, 1967 :s sheets-sheet 1 INVENTOR Nicolas SOLODUCH Feb. 24, 1970N. soLoDucHA 3,497,326

APPARATUS FOR PRoDUcING TITANIUM TETRACHLORIDE AND OTHER HALTDEs FiledJan. 18, 1967 3 Sheets-Sheet 2 INVENTOR Nicolas SOLODUCHA A TTORNE Y/Feb. 24, 1970 N, .SOLODUCHA 3,497,326

APPARATUS FOR PRODUCING TITANIUM TETRACHLORIDE AND OTHER HALIDES FiledJan. 18, 1967 d# 3 Sheets-Sheet 5 ATTORNEY United States Patent O3,497,326 APPARATUS FOR PRODUCING TITANIUM TETRACHLORIDE AND OTHERHALIDES Nicolas Soloducha, 4051 Harvard Ave., Montreal, Quebec, CanadaFiled Jan. 18, 1967, Ser. No. 610,173 Int. Cl. B07b 9/02; C01g 23/02;C01b 9/02 U.S. Cl. 2.3-284 8 Claims ABSTRACT OF THE DISCLOSURE Anapparatus for producing titanium tetrachloride and other halides fromfinely divided titanium bearing ore is provided. The apparatus comprisesa plurality of interconnected hollow tubular links disposed insubstantially vertical alignment and interconnected one to the other toform an elongated spiral, each of said tubular links having first andsecond gas conducting passages interconnected at their upper ends andeach having a gas distributing chamber disposed adjacent the lower endof said first gas conducting passage, gas feeding means leading intosaid gas distribution chamber, material feeding means and materialpreheating means connected into each link adjacent the beginning of saidfirst gas conducting passage and in advance of said gas distributingchamber, and gas by-pass means leading from the connection between upperends of said rst and second passages to adjacent the lower end of atleast one of said passages to permit recirculation of heavier particlesof said materials said by-pass means in said second and subsequent linksextending from the said connection between said first and second gasconducting passages to a connection to a solid particle collectorexteriorly of said links or alternatively to a connection with the saidsecond gas conducting passage adjacent its lower end, and damper meanscontrolling said by-pass connections.

This invention relates to an apparatus for the production of titaniumtetrachloride and other halides. More particularly, this inventionrelates to an apparatus for the chlorination of linely powdered titaniumbearing material having a maximum particle size of 150 mesh and moreparticularly those materials having a maximum particle size of 325 meshwith the bulk being particles of one micron or submicron crystal sizes.

At the present time, two methods are commonly employed for the largescale manufacture of titanium tetrachloride:

(a) The older method in which the rutile or other ground titanium ore ismixed with ground charcoal or petroleum coke, the mixture brickettedwith pitch, the brickettes baked at 500800 C. and chlorinated at 700-l000 C. in shaft kilns;

(b) The second and more recent method in which the closely sized rutileis intimately mixed with powdered coke or charcoal and is chlorinated at800-1000 C. in a uidized bed with chlorine.

In utilizing method a, the initial bricketting is expensive and the useof pitch (a source of hydrogen) in combination with chlorine formshydrochloride gases which leads to corrosion problems. The newer methodb of course eliminates these problems but is still not satisfactory withrespect to ne powdered material. The method b is practiced commerciallywith chlorination of material of a grain closely sized from 20 to 150mesh of rutile in fluidized beds. In this process smaller particles, forexample, minus 150 mesh are blown out of the reactor and accordinglypresent a waste. As is known, chlorination in a fluidized bed is inpractice the bubbling of chlorine gas through a bed of closely sizedrutile or other titanium bearing materials.

3,497,326 Patented Feb. 24, 1970 ICC As an attempt to overcome theproblem of wastage of fine powdered material in a process of thisnature, S. S. Cole and L. W. Rowe in U.S. Patent No. 2,555,374, issuedJune 5, 1951, proposed iiash chlorination of very finely divided metaloxides by charging the finely divided charged material into the bottomof an established bed of optimum sized rutile, ilmenite or even an inertmaterial such as sand. Chlorination should occur before the dust passesthrough the bed. The major requirement is that the bed be lesschlorinatable than the charge. For example, a

charge al1 minus 50 microns size, is blended with 20% weight basisground to 20-60 mesh coke and fed to the bottom of the bed with thechlorine gas stream. Check Valves must be used to permit entry of thecharge and prevent the bed from discharging when the gas flow is cutoff. Such check-valves are a source of trouble during the chlorinationat temperature of 600-800 C., especially with large area chlorinators.The coarse pieces of coke must be used to reduce compaction of theestablished bed of optimum size rutile, which serves as restraining bedto prevent the finely divided particles of the charge and chlorine topass too early through the iluidizedbed.

Although chlorination of finely divided particles should proceed muchfaster than the bigger particles of rutile, it was found in practicethat chlorination in a restraining bed of 20 to 150 mesh sizes of rutilethat only about 22 lbs. of finely divided beneliciated titanium materialTiO2 and 2.6% FeO) could be chlorinated per square foot per hour byflash chlorination in an experimental small chlorinator.

VSuch small quantities of chlorination per square foot area ofchlorinator can be explained as a large volume of the chlorinator isoccupiedby the restraining bed of rutile which practically does not takepart in the chlorination process. It is possible in large units, withdeeper restraining bed, to speed the chlorination per square foot areaper hour of chlorinator by speeding the flow of chlorine and chargedsolids. However, the deeper restraining bed will set in a similar way asthe filter medium in any filter; this is to keep the solids at the lowerpart of the restraining bed and the larger part of chlorine at thehigher speed of the gases will escape the chlorination due to lack ofcharge on the top of the bed. The efficiency of utilization of chlorinewill be lowered considerably.

It is well known that the titanium material contains compounds ofalkaline earth or alkali metals that upon chlorination produce chloridesalts of these materials in the molten form. Such molten chlorides coatthe particles present in the reactor bed and destroy the efiiciency ofthe reaction. The presence of alkaline earth or alkali metal chloridesin fluidized bed of the chlorinator can plug and cement the reactorcompletely. I. I. Krchma in his U.S. Patent No. 2,701,180 proposes tochlorinate titanium bearing material with alkali earth and alkali metalcompounds such as titanium slag, which contains from five to fifteenpercent of such compounds, by removing continuously frorn the reactionzone of a fluidized bed a suiiicient portion of solids of said iluidizedbed (up to seven parts per one part of charged slag); then waterleaching the solids thus removed, washing and drying the leached productand returning said purified dried solids to the reaction zone again forchlorination in fluidized bed. This process is very costly andcumbersome.

The same can be said, concerning the flash chlorination in restrainingbed described in U.S. Patent No. 2,555,374. The flash chlorinationcannot be effectively applied for' finely divided titanium bearingmaterial, minus mesh or less, without continuously removing a suflicientportion of charged material and a part of restraining bed, from three tofive parts by weight per part of charged material, if the chargedmaterial contains one or more percent of impurities such as calcium,magnesium, or aluminum compounds.

Many other attempts have been made to overcome these and other problemstand many patents have issued showing processes and apparatus forchlorination of titanium bearing materials, as for example thefollowing:

U.S. Patents Nos. 1,179,344 L. E. Barton, Apr. 18, 1916, 1,707,257Charles de Bomden, Apr. 2, 1929, 1,845,342 B. D. Saklatwalla, Feb. 16,1932, 2,184,884 I. E. Muskat and R. H. Taylor, Dec. 26, 1939, 2,184,885I. E. Muskat and R. H. Taylor, Dec. 26, 1939, 2,184,887 I. E. Muskat andR. H. Taylor, Dec. 26, 1939, 2,378,675 W. Y. Agnew, June 19, 1945,2,463,396 I. J. Krchma, Mar. 1, 1949, 2,533,021 I. J. Krchma, Dec. 5,1950, 2,555,374 L. W. Rowe and S. S. Cole, June 5, 1951, 2,701,179 R. M.McKinney, Feb. 1, 1955, 2,701,180 I. J. Krchma, Feb. l, 1955, 2,747,987J. M. Daubenspeck and R. S. McNell May 29, 1956, 2,758,019 J. M.Daubenspeck and R. D. Tooney, Aug. 7, 1956, 2,855,273 A. W. Evans etal., Oct. 7, 1958, 3,101,249 J. C. Priscu, Aug. 20, 1963, 3,149,911 E.Fornasieri et al., Sept. 22, 1964.

Canadian Patents Nos. 221,537 G. Gartered and M. Devaux, Aug. 1, 1922,377,396 D. H. Dawson et al., Nov. 1, 1938.

The applicant, being aware of these patents and other prior art, hasdeveloped a novel process and apparatus whereby most of the problems anddisadvantages of the preceding art have been overcome. Morespecifically, I have found that the chlorination of finely dividedtitanium bearing material such as, leach product obtained by pressureleaching ilmenite or from titanium slag or directly rutile or Sorel slagground to minus 150 mesh, and in one embodiment to minus 325 mesh can-be chlorinated with maximum eiciency and results, in a continuousprocess according to this invention. Wherein a gas stream of chlorine isprovided and solid particles of finely divided titanium material andcarbon are fed into and suspended in said gas stream in a circulatingcycle which can be repeated as many times as required to obtain thedesired complete chlorination. In this process in the first stage ofchlorination (at temperatures of 600-1000 C.), the reaction2TiO2-l-Cl2-l-3C=2TiCl4+2COiCO2 takes place when solid particles oftitanium material and carbon strike each other in the stream of chlorinegas; in the second end stage of chlorination (at temperatures of 1000 C.or over) the chlorination is nished according to the equationTiO2+2Cl2l2CO=TiCl4l2CO2. In this way full chlorination can be achievedwith nearly 100% utilization of charged chlorine and solid TiOZ. The endproducts of such chlorination will Ibe only gases of titaniumtetrachloride, carbon monoxide and minor amounts of carbon dioxide andother gases.

As is well known, the chlorination of titanium bearing material proceedsaccording to the following reaction equation and the free energy changeslisted in Table I below.

The carbon or carbon monoxide play an important part as reductant in thechlorination, since without carbon the reaction is difticult as it canbe seen from the free energy change of Equation 4.

Thermodynamical considerations show that for the chlorination oftitanium bearing material a mixture of carbon -monoxide and chlorinesho-nld prove to be as eiiicient as chlorine in the presence of carbon.But the experiments show that the velocity of chlorination with amixture of carbon monoxide and chlorine is slower below 1000 C. thanwith carbon and chlorine, and that this velocity is proportional to theCO content, but independent of the C12 concentration, whereas thevelocity of chlorination with carbon and chlorine is proportional to theC12 content and independent of the CO content of the gase phase. At 1000C. or over the chlorination with the mixture of car-bon monoxide andchlorine is faster and is independent of the chlorine content, Thereforethe last traces of the chlorine and titanium material at thistemperature can be chlorinated and utilized in the stream of carbonmonoxide if the ratio of the charge of chlorine and titanium material isproperly adjusted. The desired maximum eiiiciency of hundred per cent ofchlorination can be achieved under ideal conditions.

The many uses of titanium tetrachloride are well known; one such usebeing in the production of pigments for rubber, paints, plastics etc.

The process of the invention will be more fully understood by referenceto the following detailed description and as illustrated by reference tothe accompanying drawings showing a preferred form of apparatus by meansof which the process may be carried out, and in which;

FIGURE l is a front view of a multi-cycle circulating flow apparatusaccording to the invention having a plurality of interconnected tubulargas conducting links in elongated spiral relationship with gas andmaterial feeding, discharge, and control devices.

FIGURE 2 is a top plan view of the apparatus of FIGURE 1.

FIGURE 3 is a sectional view of FIGURE 2 as seen along the lines 1 1 and6 6 showing the structure of the rst link in more detail particularlythrough the feeding and preheating arrangements.

FIGURE 4 is a typical section of the second or any following link of theapparatus as seen along the lines 2 2, 3 3, 4 4 and 5 5 of FIGURE 2.

'FIGURE 5 is a typical section of the upper elbow on each interconnectedlink as seen along the line 6 6 of FIGURE 2.

FIGURE 6 is a cross section of the elbow construction shown in FIGURE 5as seen along the line 7 7.

With reference to the drawings, the chlorination apparatus is shown ascomprising several interconnected hollow tubular links (iive shown)forming an elongated spiral to which is connected, at the bottom of eachlink, gas distributing chambers with nozzles for chlorine and othergases. In addition, the first link of the spiral arrangement has feedingand preheating devices as will be described below.

In order that the main elements of this apparatus may be clearlyunderstood reference will be made to the drawing FIGURES 1, 2, 3, 4 and5 where 11 indicates the rst link of the spiral chlorinator and 12, 13,14 and 15 the second, third, fourth and fth link respectively as shownin FIGS. l and 2. The number of links forming the spiral can be as manyas required, five being shown in the present drawing, On FIG. 3, whichis a section of line 1 1 ('FIG. 2) of the first link 11, 16 representsthe gas distributing chamber with nozzles 17 which is typical for theother chambers of the following links indicated by the same numbers inFIG. 4, which differ only in the area and quantity of nozzles in eachchamber which must be made to suit the quantity of chlorine and othergases required to pass to each link of the spiral. On each chamber 16 anopening 18, with valve 19 and distributing pipe 20 is provided forsupplying chlorine gas under pressure, for chlorination, at the bottomof each link. On the opposite side of each chamber 1-6 another opening21, with valve 22 and distributing pipe 23 is provided for supplyingcarbon monoxide under pressure.

On each chamber 16 lower elbows 24 and 27 of the successive spiral linksare mounted. For the rst link (FIG. 3) an elbow 24 with receiving port25 and opening 26 is provided. For the following links of the spiral, asshown in FIG. 4, a typical elbow 27 with port 28 is provided. Two hollowupright cylindrical members 29 and 30 are mounted on the lower elbow ofeach link of the spiral. The two cylindrical members 29 and 30 areconnected on the top with an upper elbow 31, typical section of which isshown of FIGS. and 6. The upper elbow 31 must not only fit the diametersof each members 29 and 30 but it must have at the turning point of theelbow 31 a widening of the inside area 32 and provided lwith an opening33.

To each such upper elbow opening 33 a downwardly extending pipe isconnected. For the first link a pipe 60 makes connection between theopening 33 of upper elbow 31 and the opening 26 of lower elbow 24. Toall other openings 33 of the following links of the spiral, a pipe 61 isconnected in downward direction, with a flap type valve or damper -62which controls flow through this pipe into two branches 63 and 64, fromwhich 63 is directed to the hollow cylindrical member 30 of thepreceding link and the second branch 64 is connected with a collector 65with release valve A66. This arrangement is provided for recycling largeparticles back for a second circulation cycle in the link andaccordingly repeated chlorination and for rejecting by pipe 64 anyundesirable particles such as silica and other impurities, the selectionbeing made by the valve 62.

For feeding of the solid charge to the lower elbow 24 a combustionchamber 34 is connected with a feeding device 35, comprising a lock typefeeder 36, with hopper 37, an injector 38 with nozzle 39, and regulatingvalve 40, and inlet pipe 41. For preheating a solid charge in thechamber 34, a Aburner 42 is provided with an air injector 43, regulatingvalve 44 and inlet pipe 45. If powdered petroleum coke or charcoal isburned, a lock type feeder 46 with hopper 47 is used, or if carbonmonoxide is to be burned the gas will be delivered by the pipeline 48with regulating valve 49 from distributing pipe 23 to burner 42.

To the lower elbows 27 of each succeeding spiral links, as shown on FIG.4, is mounted a gas -burner 50 comprising an injector 51, regulatingvalve 52, inlet pipe 53 for air or other gas and pipeline 54 withregulating valve 55 for delivering carbon monoxide from pipe 23 to eachburner 50, if required. As is known, the burner 42 as well as burners 50must have ignition devices, for example, high intensity electrical sparkignition devices (not shown).

As is shown most clearly in the sections of FIGURES 2, 3, 4 and 5, allparts making up the links of the present spiral chlorinator are providedwith jacketed steel shells (see for example, 129, 131, FIGURES 3 and 4),and lined inside with acid and refractory resistance material (29a, and30a, and 31a of FIGS. 3-4) to provide moderate thickness of lining. Thejacketed shells 129-131 are furnished with inlets 70 and outlets 71, forcooling medium circulation. This cooling arrangement, the jacketed steelshells and the inside brick lining of moderate thickness are necessaryto keep the inside walls of the lining at temperatures between 40G-800C. In this way, the brick lining at this temperature will be coveredwith chloride impurities having high temper-ature melting points and thelining will be protected from attack by the hot chlorine.

It is possible to make the interconnected links of the spiralchlorinator with jacketed shell from steel without the brick lining.Since by intensive cooling the steel wall of inside shell of spiral canbe kept at low temperature at which temperature the steel wall will alsobe covered with high temperature melting chlorides and prevented in thisway from further attack of hot chlorine. However, without the bricklining the heat losses by cooling will not be permissible for properoperation of the chlorination without burning additional fuel.

In the first stage of chlorination and to keep the solids in gassuspension, the speed of the owstream of the gases in the cylindricalmembers of the first and partly in the second link of the chlorinatormust be maintained higher than those required in the following stages ofchlorination where the solid particles will have been diminished tomillimicron sizes and therefore can be kept in gas suspension with avery low speed of flow gases, for example, about one-half foot persecond. Taking into consideration what was mentioned above and thevolume changes from chemical reactions and from temperature rises duringthe chlorination, the diameters of the members making up each next linksfollowing the first link must be proportionally enlarged from 10 to 30%,depending on quantity of links in spiral, so as to have in the last linkcylindrical mem-bers of four to five times larger area than those in thefirst link. The passage area of lower elbows 24 and 27 should be builtsmaller in diameter than the cylindrical members and upper elbows. Inthis way, the required higher speed of the flowing gases can `beachieved in the lower elbows, and the injection of carbon monoxide orother gases in the second and following spiral links which is requiredto accelerate solid particles suspended in the gas stream can be broughtto a minimum.

One TiOz bearing ore which is suitable for use in my process, thoughunsuitable for use in the processes of the prior art, obtained bypressure leaching ferrotitanium ores is at high temperature with dilutesulphuric acid or hydrochloride acid or by selective chlorination. Thisore has a maximum particle size in the range of minus 50 microns (oraround minus 325 mesh) with the major portion of the ore having a muchsmaller particle size ranging from a few microns to su-bmicron sizes. Asan example the leach product from St. Urbain ilmenite has the followinganalysis:

All are in minus 50 micron crystal sizes from which over 60% is minus 3microns.

Operation Before starting chlorination, the combustion chamber 34 andthe entire inside wall of chlorinator must be heated to about 800 C. byburning powdered coke, charcoal, or carbon monoxide using burner 42, airinjector 43 and lock type feeder 46 if powdered carbon from hopper 47 isburned. If carbon monoxide is burned, this gas can be taken from pipe 23through pipe 48 by opening the regulating valve 49 and air injectorvalve 44. Then the finely divided titanium bearing material of minus 150mesh blended with a minimum of 10% to a maximum of 50% by weight ofground to 150 mesh coke or charcoal, is continuously fed through thehopper 37 and lock type feeder 36 and injected into the ame stream ofburning gases in chamber 34 by a jet of cornpressed chlorine or carbonmonoxide or air, supplied by injector 38. Simultaneously chlorine, undera pressure of about 30 p.s.i. in the distributing pipe 20, is injectedthrough the nozzles 17, in an amount stoichiometrically adjusted to thetitanium bearing material, as a jet stream as shown by arrows on FIG. 3and FIG. 4, by opening valves 19. The chlorine is directed in theupright direction of the cylindrical members of two or more of the firstlinks of the spiral, so that about 60% to of chlorine is directed tofirst and the balance to the next links. For the third, fourth and fifthlinks only monoxide gas from distributing pipe 23 need be injectedthrough the nozzles to keep the constant ow of stream of chlorinatinggases and charged solids in suspension in the chlorinator. Carbonlmonoxide also can be added partly to the first and second links tomaintain the required flow of gases and solids. The jet of incomingchlorine gas and carbon monoxide through the nozzles set up a violentagitation, interimpaction and attrition of the particles of titaniumbearing material and coke.

At the starting point of the chlorination, especially in first andsecond links, the reaction starts rapidly and takes place according tothe equations and TiO2{-2Cl2+2C=TiCl4-j2CO. In the later stages in thethird, fourth and next links, where the solid particles will diminish tomillimicron sizes and the temperature reach l000 C. or more, thechlorination will be finished according to the equation:

Chlorination in the presence of carbon monoxide is independent on thecontent of chlorine. Therefore, chlorine and titanium material can beutilized to the last traces, if the ratio of chlorine and titaniummaterial is properly adjusted and the carbon monoxide is present inexcess as the end of chlorination. It must be stressed that the streamof gases and solids in gas suspension must be kept at the lowestpossible speed in the hollow link members of the spiral chlorinator,i.e., only at the minimal speed required to prevent the solids fromsettling, and to pass the highest point of upper elbow of each spirallink.

As previously described, in each upper elbow 31, a widening of area 32is provided. By passing through this area the speed of fiow of gaseswill diminish two to three times according to the size of the enlargedarea 32. The unreactcd larger particles of charged solids will fall outof the stream and through the opening 33 to be fed by the selectivepipes 61, 63- to return to the foregoing link of spiral or to berejected. As shown on FIG.

3, in the first link 11 the big particles can return to start- I ingpoint of lower elbow 24 through opening 33, pipe 60 and opening 26 forrecirculation. The big particles of solids in the second, third, fourthand next links can be returned to recirculation through the opening 33,pipe 61, switch valve 62 and pipe 63 or by switching the valves 62,through the pipes 64, the solid particles such as silica and others canbe thrown out to collector 65 and rejected.

Not only leach products, or rutile ground to fines, but also titaniumslag, can profitably chlorinated by this method in spiral chlorinator ofthe invention without danger of plugging or cementing the reaction Zonewith molten chlorides of alkali earth metals as may occur with the knownchlorinators.

As an example, if a material such as Sorel titanium slag having highsilica and high alkali earth metal cornpounds, ground to minus 150 meshis chlorinated in gas stream of chlorine in accordance with thisinvention, the solid of silica and of earth alkali metals, chlorinationof which proceeds much slower than of titanium and iron compounds, willbe covered immediately with molten chlorides of these elements and willbe prevented from further chlorination. When they come to the end stageof chlorination where the flow speed of gases through the third, fourthand fifth links of spiral is very slow, they will be rejected throughthe pipe 64 and collector 65.

The end products of such chlorination will be gases free from chlorineand solid particles of charged materials, mostly gases of titaniumtetrachloride and minor amounts of other chlorides, carbon monoxide andcarbon dioxide gases in the approximate ratio of 80% CO to CO2 and theminor amount of neutral gases such as nitrogen and others.

The product gases after passing the chlorinator are at temperature ofabout 1000 C. and must be cooled and the titanium tetrachlorideseparated and purified. The separation and purification operation is notwithin the scope of this invention and can be accomplished by any of thewell known methods of purification and distillation of titaniumtetrachloride.

In the apparatus shown by Way of example in the present drawings, thegases from fifth link 15 go down- Ward to the cooling and first steppurification separator 72 and through the pipe 76 to furtherpurification and distillation (not shown). The cooling separator 72 withjacket 73 has inlet 74 and outlet 75 for a cooling medium, such asslightly compressed air, and outlet 77 with valve 78 for rejecting themolten chlorides of iron and other condensed in cooling separator 72.The compressed air, by passing the cooling separator 72, is heated bycooling the product gases and this heated 4air can be used to preheatthe solid charge of titanium and carbon as well as can be used aspreheated air for burning purposes. This cooling first step purificationseparator 72 can be installed in series of two or more andcountercurrent cooling units. If desired the air to be supplied to thereactor can be used as the cooling fluid thus economizing heatingrequirements.

After separation of titanium tetrachloride and other chlorides bycooling and liquefying, the carbon monoxide, carbon dioxide and othergases with about 50% of CO content can be recycled and used forchlorination and heating purposes. A part of these gases compressed toabout 30 p.s.i. with 50% of CO content will be injected through thenozzle 17, a part can be burned by burners 42 and 50 as described aboveand the balance can be used for other heating purposes. The content ofcarbon monoxide in these affluent gases can be kept at required levelsby charging more or less of carbon such as coke or charcoal as reductantwith titanium charge.

While the invention is particularly adapted for production of titaniumtetrachloride, halogenation of other similar metal oxides and productionof other halides can lalso be accomplished by the present method anddescribed apparatus, Further this process could be used for largerparticle sizes but is believed to be most operable and economicallyfeasible in the minus mesh particle size and more particularly the minus325 mesh particle size.

Obviously, many modifications and variations of the invention may bemade without departing from the essence and scope thereof and only suchlimitations as are recited in the appended claims should be applied,

I claim:

1. An apparatus for the production of titanium chloride or other halidesfrom finely divided titanium bearing material on the order of 150 meshor smaller sizes, comprising in combination, a plurality ofinterconnected hollow tubular links disposed in substantially verticalalignment and interconnected one to the other to form an elongatedspiral, each of said tubular links having first and second gasconducting passages interconnected at their upper ends and each having agas distributing chamber disposed yadjacent the lower end of said firstgas conducting passage, gas feeding means leading into said gasdistribution chamber, material feeding means and material preheatingmeans connected into each link adjacent the beginning of said first gasconducting passage and in advance of said gas distributing chamber, andgas by-pass means leading from the connection between upper ends of saidfirst and second passages to adjacent the lower end of at least one ofsaid passages to permit recirculation of heavier particles of saidmaterials, said by-pass means in said second and subsequent linksextending from the said connection between said first and second gasconducting passages to a connection to a solid particle collectorexteriorly of said links or alternatively to a connection with the saidsecond gas conducting passage adjacent its lower end, land damper meanscontrolling said by-pass connections.

2. The apparatus of claim 1 wherein said gas distribution chamber isdivided from the interior of said gas conducting passages by a perforatewall, and said gas feeding means consisting of at least one gasinjection nozzle leading into said gas distribution chamber.

3. The apparatus of claim 1 wherein said material feeding means consistsof a tubular member leading directly into the lower portion of said linkfirst gas conducting passage and controlled material delivery means andan auxiliary burner means connected to said tubular member.

4. The apparatus of claim 2 wherein said material feeding means consistsof a tubular member leading directly into the lower portion of said linkrst gas conducting passage and controlled material delivery means and anauxiliary burner means connected to said tubular member.

5. The apparatus of claim 3 wherein an auxiliary burner means isconnected into each of said second and following links adjacent thelower end of said second gas conducting passage.

6. The apparatus of claim 2 wherein an auxiliary burner means isconnected into each of said second and following links adjacent thelower end of said second gas conducting passage.

7. The apparatus of claim 1 wherein said by-pass means in said rst linkextends from the said connection between said first and second gasconducting passages to adjacent the lower end of said first gasconducting passage.

8. An apparatus as claimed in claim 1 wherein each of said tubular linksare enlarged at the point of interconnection of said rst and second gaspassages to provide a Widening of said passages at their upper ends toreduce velocity of said gas stream to such a degree that larger solidparticles of material will be dropped from said gas stream into said gasby-pass means.

References Cited UNITED STATES PATENTS 2,297,726 10/ 1942 Stephanofl:23-252 XR 2,550,390 4/1951 Stephanoif 241-5 XR 2,590,219 3/1952Stephanoff 241-5 XR 3,403,451 10/1968 Stephanotf 34-10 JAMES H. TAYMAN,JR., Primary Examiner U.S. C1. X.R.

